Fruit initiation in Helleborus niger L. triggers chloroplast formation and photosynthesis in the perianth

Differences in Vase Lives of Cut Hydrangea Flowers Harvested at Different Developmental Stages

“…Several studies have focused on decorative organs maintained after flowering, with one study that focused on hydrangea flowers (Melo et al, 1995;Salopek-Sondi et al, 2000, 2002Schmitzer et al, 2013;Tavares et al, 1998;Yoshida et al, 2008). These studies reported on photosynthesis, the relationship between sepal retention and fruit development, and pigments.…”

Reproductive Development of the Christmas Rose (Helleborus niger L.): The Role of Plant Hormones

“…It was detected at ultrastructural level where gerontoplasts were shown to be predominant plastids in the sepal cells of depistillated flowers in comparison to typical, well developed chloroplasts present in the cells of fertilized flowers of the same age. 17−19 At biochemical level, this thesis can be confirmed by several parameters such as decreased chlorophylls/carotenoids ratio, 17 elevated accumulation of H 2 O 2 and lower activities of an antioxidant enzymes in depistillated flowers in comparison to fertilized ones. 27 The most prominent elongation of flower stalk occurs at pre-anthesis when its length increased up to ten fold (from 1 to 10 cm) ( Figure 1F).…”

“…17 In the sepals of fertilized flowers chlorophyll accumulates gradually until the value of 3.5 monitored by chlorophyll meter (which correspondents to approximately 350 mg per g of FW) at stationary green stage phase ( Figure 1G). …”

“…20 A detailed botanical description can be found elsewhere. 19,21,22 The plants used in our experiments were collected at two locations through several growth seasons: habitat 1 was a natural mountain forest at Gorski kotar, Croatia (altitude: 800 m), and habitat 2 was a woodlot at the "Fran Kušan" Botanical Garden of the Faculty of Pharmacy and Biochemistry of the University of Zagreb. The Christmas rose may produce flowers from early winter up until late spring.…”

“…Details about distribution of particular cytokinin species during flower and fruit development are described earlier. 19,25 In brief, riboside monophosphates (iPRMP, ZRMP, DZRMP) peaked first, followed by the ribosides (ZR and DZR), while the free bases (Z and DHZ) were the most abundant in the last developmental stage analyzed ("Almost ripe" stage, 2-3 weeks before seed ripening). At anthesis, DZ-type cytokinins were slightly more abundant than their zeatin analogs, but, during post-anthesis, this proportion was inverted, with Z and derivatives attaining up to seven times higher concentrations.…”